<template>
  <el-dialog
    width="500px"
    title="员工导入"
    :visible="showExcelDialog"
    @close="$emit('update:showExcelDialog', false)"
  >
    <el-row type="flex" justify="center">
      <div class="upload-excel">
        <input
          ref="excel-upload-input"
          class="excel-upload-input"
          type="file"
          accept=".xlsx, .xls"
          @change="onFileChange"
        >
        <div class="drop">
          <i class="el-icon-upload" />
          <el-button type="text" @click="getUserTemplate">下载导入模板</el-button>
          <span>将文件拖到此处或
            <el-button type="text" @click="$refs['excel-upload-input'].click()">点击上传</el-button>
          </span>
        </div>
      </div>
    </el-row>
    <el-row type="flex" justify="end">
      <!-- update:props属性名，值 直接修改 .sync修饰符的属性值 -->
      <el-button size="mini" type="primary" @click="$emit('update:showExcelDialog', false)">取消</el-button>
    </el-row>
  </el-dialog>
</template>
<script>

import { downloadUserTemplate, uploadExcel } from '@/api/employee'
import { saveAs } from 'file-saver'

export default {
  props: {
    showExcelDialog: {
      type: Boolean,
      default: false
    }
  },
  methods: {
    // 获取员工导入模板
    getUserTemplate() {
      downloadUserTemplate().then(res => {
        saveAs(res, '员工信息导入模板.xlsx')
      })
    },
    // 文件域选择文件完成以后的回调函数
    onFileChange(e) {
      // console.log(e.target.files)
      const files = e.target.files
      // 如果没有选中任何文件，就停止，不往下执行
      if (!files.length) {
        return
      }
      // 创建一个formData实例对象
      // 为什么要创建formData实例对象？ 接口文档中明确说明要的就是form-data格式的文件
      const formData = new FormData()
      formData.append('file', files[0])
      // 调接口，上传excel文件，等待导入成功
      uploadExcel(formData)
        .then(() => {
          // 1. 提示用户，上传导入成功
          // 2. 弹框需要关闭
          this.$message.success('员工数据导入成功')
          this.$emit('update:showExcelDialog', false)
          // 告诉父组件，我的工作干完了
          this.$emit('done')
        })
        .catch(() => {
          console.log('上传失败')
        })
        // 不管上面是进 then 还是进 catch 最终都会进 finally
        .finally(() => {
          this.$refs['excel-upload-input'].value = ''
        })
    }
  }
}
</script>

<style scoped lang="scss">
    .upload-excel {
      display: flex;
      justify-content: center;
      margin: 20px;
      width: 360px;
      height: 180px;
      align-items: center;
      color: #697086;
      .excel-upload-input {
        display: none;
        z-index: -9999;
      }
      .btn-upload,
      .drop {
        border: 1px dashed #dcdfe6;
        width: 100%;
        height: 100%;
        text-align: center;
        line-height: 160px;
        border-radius: 8px;
        display: flex;
        flex-direction: column;
        justify-content: center;
      }
      .drop {
        line-height: 40px;
        color: #bbb;
        i {
          font-size: 60px;
          display: block;
          color: #c0c4cc;
        }
      }
    }
</style>
